stochiometry pdf

• What type of reaction is represented by K₂CrO₄ + Ba(NO₃)₂?

  Precipitation reaction
• What occurs when aqueous solutions of ionic compounds are mixed?

  A solid precipitate forms
• How can we predict the products of a precipitation reaction?

  By switching anions and cations
• What are the three types of equations in precipitation reactions?

  • Molecular equation
  • Total ionic equation
  • Net ionic equation
• What salts are always soluble according to solubility rules?

  Nitrate and acetate salts
• Which group of salts is soluble according to solubility rules?

  Alkali (group 1) salts and NH₄⁺
• Which halide salts are NOT soluble?

  Ag⁺, Pb²⁺, Hg₂²⁺
• What sulfate salts are NOT soluble?

  BaSO₄, PbSO₄, HgSO₄, CaSO₄, SrSO₄
• What type of salts are generally insoluble?

  OH^- salts
• What are the exceptions for insoluble sulfide, carbonate, chromate, and phosphate salts?

  They are generally insoluble
• What are strong acids classified as in terms of solubility?

  Soluble
• What is the stoichiometry process for precipitation reactions?

  • Write the balanced net ionic equation
  • Use traditional stoichiometry
• How do you calculate the volume of HCl needed to precipitate Ag⁺ ions?

  Use stoichiometry with concentrations
• What mass of solid is formed from mixing copper(II) chloride and sodium hydroxide?

  Calculate using stoichiometry
• What is the definition of an acid in acid-base reactions?

  Proton donor (H⁺)
• What is the definition of a base in acid-base reactions?

  Proton acceptor (usually OH^-)
• What is the general equation for a neutralization reaction?

  Acid + Base → Salt + Water
• What is a titrant in acid-base titration?

  Solution of known concentration
• What is an analyte in acid-base titration?

  Substance being analyzed
• What is the equivalence point in titration?

  When moles of acid equal moles of base
• What does the end point in titration indicate?

  Indicator changes color
• How do you calculate the concentration of LiOH after neutralization with nitric acid?

  Use volume and molarity of HNO₃
• How do you find the concentration of excess H⁺ or OH^- after mixing HCl and Ba(OH)₂?

  Calculate using initial concentrations
• What happens to the element that loses electrons in oxidation-reduction reactions?

  It is oxidized
• What happens to the element that gains electrons in oxidation-reduction reactions?

  It is reduced
• How do you identify substances oxidized and reduced in reactions?

  • Identify electron loss (oxidized)
  • Identify electron gain (reduced)
• How do you balance redox reactions in acidic solutions?

  Use half-reaction method
• What is the first step in balancing redox reactions in basic solutions?

  Balance as in acidic solutions
• What do you add to the final equation in basic solutions?

  Add OH^- equal to H⁺
• How do you form water in balancing redox reactions?

  Combine H⁺ and OH^-
• What should you check after balancing redox reactions?

  Elements and charges for balance
• What are the steps to balance redox reactions in basic solutions?

  1. Balance as in acidic
  2. Add OH^- equal to H⁺
  3. Form water by combining H⁺ and OH^-
  4. Check elements and charges for balance
• How do you balance the reaction Cu + NO₃^-?

  Use half-reaction method
• oxidation number

  • element = zero
  • ions (ionic compound) = charge of ion
• oxidation number IN A COMPOUND

  • group 1 = +1
  • group 2 = +2
  • oxygen = -2 EXCEPT in H202(peroxide)
  • hydrogen = +1 EXCEPT with group 1 or 2 -> -1
  • halogens = -1 EXCEPT with element with higher electronegativity
  • ex: clo3 = 5 = x + (-2x3) = -1
• Balancing Redox solution

  1. half equation
  2. balance the element other than O or H
  3. balance O by adding H2O
  4. balance h by adding H+
  5. balance the charges by adding elections
  6. put them together and balance the electrons